CT-adipose measures identify severe SARS-CoV-2 risk beyond traditional obesity metrics: a C4R cohort study

Higher body mass index (BMI) increases risk of respiratory failure and death from SARS-CoV-2 infection. BMI is imprecise and fails to account for adipose tissue distribution. We sought to determine whether pericardial adipose tissue (PAT), abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), or hepatic adipose deposition on pre-pandemic computed tomography (CT) scans associate with increased risk of hospitalization or death from SARS-CoV-2.

The Collaborative Cohort of Cohorts for COVID-19 Research (C4R) ascertained SARS-CoV-2 outcomes among participants from 14 US-based cohort studies. This analysis includes participants enrolled in the Jackson Heart, CARDIA, MESA, and Framingham Heart studies. C4R attempted to enroll all cohort participants who were alive on March 1, 2020 and had not withdrawn consent for cohort participation. Our primary exposure was adipose depot size measured on research CT scans performed between 2000 and 2011. Our primary outcome was time from March 1, 2020 to hospitalization or death from SARS-CoV-2 infection ascertained by self-report or active surveillance and confirmed when available, by protocolized record review.

There were 8412 participants with at least one CT adipose measure, among whom 184 events occurred over a median (interquartile range) of 547 (338-609) days. In adjusted models, both higher PAT (per doubling in PAT, HR 1.62, 95% CI 1.25-2.09) and higher VAT (per 1-standard deviation, HR.41, 95% CI 1.20-1.67) associated with greater hazards of hospitalization or death from SARS-CoV-2. Associations remained after adjustment for BMI, diabetes, cardiovascular disease, hypertension, and waist circumference. SAT was associated with hospitalization or death but not after adjustment for BMI and obesity complications. Hepatic adipose deposition was not associated with hospitalization or death.

Greater CT-measured pericardial and abdominal visceral adipose tissue were associated with increased hazards of hospitalization or death from SARS-CoV-2 independent of BMI and clinical cardiometabolic comorbidities. Further research should investigate use of CT adipose measures to quantify risk of severe disease from viral infections and to investigate mechanisms linking adiposity to lung injury.